// SPDX-License-Identifier: GPL-2.0
/* Based on Christian Brauner's clone3() example */
#define _GNU_SOURCE
#include <errno.h>
#include <inttypes.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/un.h>
#include <sys/wait.h>
#include <unistd.h>
#include <sched.h>
#include "../kselftest.h"
#include "clone3_selftests.h"
enum test_mode {
CLONE3_ARGS_NO_TEST,
CLONE3_ARGS_ALL_0,
CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG,
CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG,
CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG,
CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG,
};
static int call_clone3(uint64_t flags, size_t size, enum test_mode test_mode)
{
struct __clone_args args = {
.flags = flags,
.exit_signal = SIGCHLD,
};
struct clone_args_extended {
struct __clone_args args;
__aligned_u64 excess_space[2];
} args_ext;
pid_t pid = -1;
int status;
memset(&args_ext, 0, sizeof(args_ext));
if (size > sizeof(struct __clone_args))
args_ext.excess_space[1] = 1;
if (size == 0)
size = sizeof(struct __clone_args);
switch (test_mode) {
case CLONE3_ARGS_NO_TEST:
/*
* Uses default 'flags' and 'SIGCHLD'
* assignment.
*/
break;
case CLONE3_ARGS_ALL_0:
args.flags = 0;
args.exit_signal = 0;
break;
case CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG:
args.exit_signal = 0xbadc0ded00000000ULL;
break;
case CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG:
args.exit_signal = 0x0000000080000000ULL;
break;
case CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG:
args.exit_signal = 0x0000000000000100ULL;
break;
case CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG:
args.exit_signal = 0x00000000000000f0ULL;
break;
}
memcpy(&args_ext.args, &args, sizeof(struct __clone_args));
pid = sys_clone3((struct __clone_args *)&args_ext, size);
if (pid < 0) {
ksft_print_msg("%s - Failed to create new process\n",
strerror(errno));
return -errno;
}
if (pid == 0) {
ksft_print_msg("I am the child, my PID is %d\n", getpid());
_exit(EXIT_SUCCESS);
}
ksft_print_msg("I am the parent (%d). My child's pid is %d\n",
getpid(), pid);
if (waitpid(-1, &status, __WALL) < 0) {
ksft_print_msg("waitpid() returned %s\n", strerror(errno));
return -errno;
}
if (!WIFEXITED(status)) {
ksft_print_msg("Child did not exit normally, status 0x%x\n",
status);
return EXIT_FAILURE;
}
if (WEXITSTATUS(status))
return WEXITSTATUS(status);
return 0;
}
static bool test_clone3(uint64_t flags, size_t size, int expected,
enum test_mode test_mode)
{
int ret;
ksft_print_msg(
"[%d] Trying clone3() with flags %#" PRIx64 " (size %zu)\n",
getpid(), flags, size);
ret = call_clone3(flags, size, test_mode);
ksft_print_msg("[%d] clone3() with flags says: %d expected %d\n",
getpid(), ret, expected);
if (ret != expected) {
ksft_print_msg(
"[%d] Result (%d) is different than expected (%d)\n",
getpid(), ret, expected);
return false;
}
return true;
}
typedef bool (*filter_function)(void);
typedef size_t (*size_function)(void);
static bool not_root(void)
{
if (getuid() != 0) {
ksft_print_msg("Not running as root\n");
return true;
}
return false;
}
static bool no_timenamespace(void)
{
if (not_root())
return true;
if (!access("/proc/self/ns/time", F_OK))
return false;
ksft_print_msg("Time namespaces are not supported\n");
return true;
}
static size_t page_size_plus_8(void)
{
return getpagesize() + 8;
}
struct test {
const char *name;
uint64_t flags;
size_t size;
size_function size_function;
int expected;
enum test_mode test_mode;
filter_function filter;
};
static const struct test tests[] = {
{
.name = "simple clone3()",
.flags = 0,
.size = 0,
.expected = 0,
.test_mode = CLONE3_ARGS_NO_TEST,
},
{
.name = "clone3() in a new PID_NS",
.flags = CLONE_NEWPID,
.size = 0,
.expected = 0,
.test_mode = CLONE3_ARGS_NO_TEST,
.filter = not_root,
},
{
.name = "CLONE_ARGS_SIZE_VER0",
.flags = 0,
.size = CLONE_ARGS_SIZE_VER0,
.expected = 0,
.test_mode = CLONE3_ARGS_NO_TEST,
},
{
.name = "CLONE_ARGS_SIZE_VER0 - 8",
.flags = 0,
.size = CLONE_ARGS_SIZE_VER0 - 8,
.expected = -EINVAL,
.test_mode = CLONE3_ARGS_NO_TEST,
},
{
.name = "sizeof(struct clone_args) + 8",
.flags = 0,
.size = sizeof(struct __clone_args) + 8,
.expected = 0,
.test_mode = CLONE3_ARGS_NO_TEST,
},
{
.name = "exit_signal with highest 32 bits non-zero",
.flags = 0,
.size = 0,
.expected = -EINVAL,
.test_mode = CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG,
},
{
.name = "negative 32-bit exit_signal",
.flags = 0,
.size = 0,
.expected = -EINVAL,
.test_mode = CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG,
},
{
.name = "exit_signal not fitting into CSIGNAL mask",
.flags = 0,
.size = 0,
.expected = -EINVAL,
.test_mode = CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG,
},
{
.name = "NSIG < exit_signal < CSIG",
.flags = 0,
.size = 0,
.expected = -EINVAL,
.test_mode = CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG,
},
{
.name = "Arguments sizeof(struct clone_args) + 8",
.flags = 0,
.size = sizeof(struct __clone_args) + 8,
.expected = 0,
.test_mode = CLONE3_ARGS_ALL_0,
},
{
.name = "Arguments sizeof(struct clone_args) + 16",
.flags = 0,
.size = sizeof(struct __clone_args) + 16,
.expected = -E2BIG,
.test_mode = CLONE3_ARGS_ALL_0,
},
{
.name = "Arguments sizeof(struct clone_arg) * 2",
.flags = 0,
.size = sizeof(struct __clone_args) + 16,
.expected = -E2BIG,
.test_mode = CLONE3_ARGS_ALL_0,
},
{
.name = "Arguments > page size",
.flags = 0,
.size_function = page_size_plus_8,
.expected = -E2BIG,
.test_mode = CLONE3_ARGS_NO_TEST,
},
{
.name = "CLONE_ARGS_SIZE_VER0 in a new PID NS",
.flags = CLONE_NEWPID,
.size = CLONE_ARGS_SIZE_VER0,
.expected = 0,
.test_mode = CLONE3_ARGS_NO_TEST,
.filter = not_root,
},
{
.name = "CLONE_ARGS_SIZE_VER0 - 8 in a new PID NS",
.flags = CLONE_NEWPID,
.size = CLONE_ARGS_SIZE_VER0 - 8,
.expected = -EINVAL,
.test_mode = CLONE3_ARGS_NO_TEST,
},
{
.name = "sizeof(struct clone_args) + 8 in a new PID NS",
.flags = CLONE_NEWPID,
.size = sizeof(struct __clone_args) + 8,
.expected = 0,
.test_mode = CLONE3_ARGS_NO_TEST,
.filter = not_root,
},
{
.name = "Arguments > page size in a new PID NS",
.flags = CLONE_NEWPID,
.size_function = page_size_plus_8,
.expected = -E2BIG,
.test_mode = CLONE3_ARGS_NO_TEST,
},
{
.name = "New time NS",
.flags = CLONE_NEWTIME,
.size = 0,
.expected = 0,
.test_mode = CLONE3_ARGS_NO_TEST,
.filter = no_timenamespace,
},
{
.name = "exit signal (SIGCHLD) in flags",
.flags = SIGCHLD,
.size = 0,
.expected = -EINVAL,
.test_mode = CLONE3_ARGS_NO_TEST,
},
};
int main(int argc, char *argv[])
{
size_t size;
int i;
ksft_print_header();
ksft_set_plan(ARRAY_SIZE(tests));
test_clone3_supported();
for (i = 0; i < ARRAY_SIZE(tests); i++) {
if (tests[i].filter && tests[i].filter()) {
ksft_test_result_skip("%s\n", tests[i].name);
continue;
}
if (tests[i].size_function)
size = tests[i].size_function();
else
size = tests[i].size;
ksft_print_msg("Running test '%s'\n", tests[i].name);
ksft_test_result(test_clone3(tests[i].flags, size,
tests[i].expected,
tests[i].test_mode),
"%s\n", tests[i].name);
}
ksft_finished();
}
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